PTB.S4.Q5 - The most reliable way to detect the presence ...

Lsacker99

Wouldn't the inability to detect methane in the atmosphere (C) be the answer? The right answer (B) says that not all living beings have the ability to produce methane, but couldn't "not all" still mean that 99.9% of living beings could (and hence NOT weaken the argument)

Admin Note: Edited title. Please use the format "PT#.S#.Q# - brief description of question."

Matt Sorr

Which question?

kellimccarthy20

I am struggling with the same question. I also picked AC C. Did you ever figure out why B is correct?

Clemens_

If there are some living things that do not produce methane, then these living things are in principle are undetectable through a search for methane. 'Some' could mean 1% or it could be 99%. Thus, answer choice (B) definitely weakens, the precise extent of its weakening power just remains undetermined.

By contrast, answer choice (C) just says that WE humans beings AT THIS PARTICULAR MOMENT are incapable of looking for atmospheric methane. This is an answer choice about our present abilities, not an answer choice about methane examination as a method of life detection. Even if we right now might not be advanced enough to detect atmospheric methane, this says nothing at all about the capabilities of this method itself. Looking for methane might still be the best method for finding life, we just might not be able to use it right now.